Method for creating printing data applied to a printer capable of generating ink droplets of different sizes

A method for creating printing data of an image to be printed, wherein the created printing data is applied to a printer that is capable of generating ink drops of different sizes, the method comprising the acts of:

• defining “P” as kinds of the ink drops sizes that the printer generates;
• defining “N” as an allowable quantity of ink drops that the printer ejects onto a pixel;
• creating a halftoning threshold table according to all combinations of P and N, wherein there are a total of (N+1)P kinds of combinations of the N and P, and each combination corresponds to one color density level;
• and
• performing a halftoning encoding process based on the created halftoning threshold table, wherein each tone value of the image to be printed is classified to one color density level thus to locate a corresponding combination, wherein the combination is represented by a series of binary bits as an encoded result to be applied to drive the printer;
• wherein P and N are both positive integers and greater than zero.